<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Document</title>
  <style>
    body {
      margin: 0;
    }

    #box {
      width: 100px;
      height: 100px;
      margin: 50px;
      border: 30px solid red;
      padding: 10px;
      background-color: green;
    }
  </style>
</head>
<body>
  <div id="box">
    
  </div>
  <script>
    // client
    var box = document.getElementById('box');
    // clientLeft  是border-left 的宽度
    // clientTop    border-top 的宽度
    console.log(box.clientLeft);
    console.log(box.clientTop);


    // 获取大小   包括padding  但是不包括边框
    console.log(box.clientWidth);
    console.log(box.clientHeight);

    // offsetWidth   offsetHeight     包括padding和边框

  </script>
</body>
</html>
